Nutritional composition of maize grain associated with phosphorus and zinc fertilization

Abstract

As an important staple food, the nutritional quality of maize grain can directly influence human health. Protein, amino acid, fatty acid, starch, antioxidant (carotenoids and tocopherols), mineral elements, and antinutrient profiles and concentrations in maize grain were evaluated under three phosphorus (P) (0, 25, and 100 kg P ha−1) and two zinc (Zn) applications rates (0 and 11.4 kg Zn ha−1). The results showed that the concentrations of crude protein, essential and nonessential amino acids, unsaturated fatty acids, carotenoids, P, and phytic acid were significantly increased by 25 kg P ha−1 application, and higher P application (100 kg P ha−1) did not result in continuous increases in these qualities. High application of P (100 kg P ha−1) significantly decreased Zn, Fe, and tocopherol concentrations compared with no P application. Zinc application significantly increased the concentrations of Zn, crude protein, and tocopherols in maize grain. These results suggest that on the basis of realizing high yield, optimal combinations of P (25 kg ha−1) and Zn (11.4 kg ha−1) fertilization can produce maize grain with higher concentrations of protein, essential amino acids, unsaturated fatty acids, starch, carotenoids, tocopherols, and mineral elements (Zn, Fe, and P).